Sistema sexual e biologia floral de Pouteria ramiflora e P. torta (Sapotaceae)

pouteria ramiflora and p. torta are tree species sympatric in the cerrado and were studied in the natural reserve of clube ca？a e pesca itororó (uberlandia-mg) in order to compare various aspects of their reproductive biology. the phenophases were evaluated weekly and their intensity was quantified. the floral biology, breeding system, sexual system and floral visitors were studied in the field and/or laboratory. in both species, leaf fall occurred in the end of the dry season, leaf flushing between the dry and the rainy season, flowering in the dry season and fruit maturation during the rainy season. they have tubular small greenish flowers, with small amounts of nectar and high pollen viability. they are self-sterile, non-agamospermic and had low fruiting success from natural pollination. p. torta is a hermaphrodite species, with protogynous and hercogamous flowers, while p. ramiflora is morphologically gynomonoecious but functionally unisexual. the apparently low pollen flow and the abortion of young fruits resulted in low fruit set from natural pollinations. both species are visited by several small insects, including butterflies, moths, flies and bees.